Diesel fuel warmer



FIG. 1 is a front elevational view of a diesel fuel warmer, showing my new design;

FIG. 2 is an end elevational view, the opposite end being a mirror image thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a top plan view, the bottom view being a mirror image thereof. 

The ornamental design for a diesel fuel warmer, as shown and described. 